A model of the cognitive process of natural language processing has been developed using the
formalism of generalized nets. Following this stage-simulating model, the treatment of information inevitably
includes phases, which require joint operations in two knowledge spaces – language and semantics. In order to
examine and formalize the relations between the language and the semantic levels of treatment, the language is
presented as an information system, conceived on the bases of human cognitive resources, semantic primitives,
semantic operators and language rules and data. This approach is applied for modeling a specific grammatical
rule – the secondary predication in Russian. Grammatical rules of the language space are expressed as
operators in the semantic space. Examples from the linguistics domain are treated and several conclusions for
the semantics of the modeled rule are made. The results of applying the information system approach to the
language turn up to be consistent with the stages of treatment modeled with the generalized net.